Interchangeable mask arrangement for photographic printers



July 21, 1959 J. s. POLLOCK ET AL 2,895,396

INTERCHANGEABLE MASK ARRANGEMENT FOR PHOTQGRAPHIC PRINTERS Filed June 13, 1957 3 Sheets-Sheet 1 John 5*. P0 llo clc illard R.Amann INVENTORS wars y 1959 J. s. POLLOCK ETAL 2,895,396 INTERCHANGEABLE MASK ARRANGEMENT FOR PHOTOGRAPHIC PRINTERS Filed June 13, 1957 s Sheets- Sheet 2 Johns. Pol lo ck WillardRAmann INVENTORS' Y {Ma/.1

ATTORNEY United States Patent INIERcHA GEABLE MASK ARRANGEMENT Fon rnorocnarmc PRINTERS John S. Pollock and Willard 'R. Amann, Rochester, N. assignors to Eastman Kodak Company, Rochester, N.Y., a corporation of New Jersey Application June 13, 1957, Serial No. 665,534

' 12 Claims. (CI. 95-49,

The present invention concerns photographic projection printers and more particularly concerns means for changing printing masks in such printers in room light.

In projection printers, the size of the printing aperture frequently is adjusted by placing removable printing masks, having apertures of the various sizes, between the light source and the printing paper. When the operator wishes to change the size of the aperture he removes one mask and replaces it with another having a different aperture.

A typical photographic printer of the above type is enclosed in a light-tight cabinet and its operation is controlled from outside of the cabinet by an operator standing in a lighted room. It has been necessary in the past, in order to change masks in such a printer, to extinguish the room light and open the cabinet. To eliminate this inconvenience, it is a primary object of the present invention to provide means whereby printing masks may be changed in room light. A related object is to change printing masks-without opening the cabinet doors of the printer. A further object is to insert and remove printing masks through a light-tight slot in the printer cabinet.

In projection printers, the best printing results are achieved when the printing paper is pressed into the image plane by a platen or like mechanism. The sharpest masking is achieved when the mask also is in the image plane, in faceto-face contact with the paper. It will be evident that when a mask is inserted into the image plane of a printer and into face-to-face contact with the printing paper, the leading edge of the mask and the trailing edge of its aperture tend to engage the printing paper and tear it. When masks are changed by opening the printing cabinet, after darkening the printing room, the printing paper may be moved manually out of the image plane until the masks are changed. On the other hand, if the masks are changed through a slot in the printer cabinet, other means must be provided for removing the paper from the image plane during the changing operation. Accordingly, it is an object of the present invention to automatically move the printing paper from its normal printing position during a mask-changing operation. More specifically it is an object of the invention to change the vertical disposition of the front edge of the printing paper in response to the insertion or the removal of a mask. In order to achieve the latter two objects, the

illustrated embodiment of the invention includes a struc the drawings, wherein:

Fig. 1 is an explodedv perspective view of the platen, a typical mask and a supporting base member;

Fig. 2 is a right side view of the mask-changing mechanism and printer cabinet showing the relative disposition of parts during the removal or insertion of a mask;

Fig. -3 is the same view as Fig. 2 showing the relative disposition of parts when the mask is seated;

Fig. 4 is a top view of the mechanism when the parts are positioned as shown in Fig. 2; and

Fig. 5 is a top view of the mechanism when the parts are positioned as shown in Fig. 3.

The present invention is illustrated in the environment of a projection printer in which the printing lamp is located near the bottom of a closed cabinet and in which negatives are-inserted into a lower portion of the cabinet above the lamp. Theprinting paper is threaded from a feed roll to a winding .roll over an aperture in a base member that is located in the upper portion of the cabinet. The base supports a platen which guides the paper and normally maintains it in the image plane of the printer. The invention relates primarily to the structures of the base and platen and to the structure of interchangeable printing masks which are adapted to be inserted between the base and the platen. The mountings for the printing lamp and negative, and the mechanism for advancing the printing paper constitute no part of the invention and are neither shown nor described herein.

Referring to Figs. 1, 3 and 5, a base 10 is rigidly mounted on a frame member (not shown) of the printer cabinet such that an edge 12 of the base faces toward a front wall or door 50 of the cabinet. A pair of U-shaped brackets 16 and 22 are mounted on opposite side faces of base 10 overhanging a rear edge hereof. Each bracket 16 and 22 has a respective front post 18 and 24 and a respective rear post 20 and 26 rising vertically from the body of the bracket. Front posts 18 and 22 are spaced from the respective rear posts 20 and 26 to receive and support a pair of laterally extending arms 28 of a platen 30. Arms 28 are located at the rear edge of the platen and act as a horizontal axis about which the platen may be rocked for the purpose set forth hereinafter. The platen has a front cut-out area 31 (Fig. 1) and a rear cut-out area 33 adapted for use with mechanism which is auxiliary to the printer and unrelated to the present invention.

Each arm 28 of platen 30 supports a respective end guide 32 through which a continuous web of printing paper 34 is threaded. The paper is threaded over guides 32 and under the platen body. During operation of the printer the platen is in a horizontal position, as shown in Figs. 3 and 5, where its weight presses the paper 34 into engagement with the upper surface of a mask 40. The mask has an aperture 42 overlying an aperture 13 in base member 10 and is supported by the base on the periphery of aperture 13. The upper face of the mask and the lower face of the printing paper lie in the image plane of the printer when the platen is in its horizontal position. The image of a negative is projected upwardly through apertures 13 and 42 onto the paper.

When platen 30 is in its horizontal position, a camming member 36, which is integral with the platen, extends through a mating slot 44 in mask 40 and seats in a notch 14 in base 10. Camming member 36 cooperates with the leading edge 41 of mask 40 when the latter is inserted into the printer and raises the front edge of the platen, thereby rocking the platen about its rear edge in brackets 16 and 22. Since the printing paper 34 is threaded through guides 32 of the platen, it rocks with the platen and the front edge 35 of the paper is thereby raisid out of the path of the leading edge 41 of the mas Figs. 2 and 4 show a mask partially inserted into the printer. A slot 52 in the front wall or door 50 of the printer cabinet is lined with plush, as indicated at 54,

to render the slot light-tight. Mask 40 is inserted into the cabinet through slot 52 and engages an upwardly inclined surface 11 (see also Fig. 1) of the front edge 12 of base 10. Surface 11 and slot 52 direct the mask between a pair of front guides 17 mounted on opposite sides of base 10. Each guide 17 has a vertical surface 19 intersecting a downwardly inclined surface 21. Surfaces 19 and 21 cooperate with slot 52 to maintain mask 40 in a horizontal plane and in alignment with base and platen 30. Before the leading edge 41 of the mask enters guides 17 it engages an inclined lower front surface 38 of camming member 36 and begins to raise the camming member to thereby rock the platen and printing paper upwardly about the rear edge of the platen.

Referring particularly to Fig. 2, it will be seen that the front vertical posts 18 and 24 of the respective brackets 16 and 22 are in lateral alignment with each other while the rear posts and 26 are not. The left arm 28 of platen 30 fits closely bet-ween posts 18 and 20 but the right arm 28 fits loosely between posts 24 and 26. When the mask is seated, as shown in Figs. 3 and 5, the right arm 28 rests against the front post 24, leaving a space 27 between the arm and the rear post 26.

Referring back to Figs. 2 and 4 when mask 40 engages the lower surface 38 of camming member 36 the friction between the mask and the camming member is such that the mask forces the entire right side of the platen rearwardly until the right arm 28 of the platen engages the rear post 26 of bracket 22. This cants the bracket counterclockwise (as viewed in Fig. 2) and moves the camming member slightly to the right of its seated position. When the mask continues to move toward the rear of the cabinet and the leading edge of slot 44 rides under camming member 36, a shoulder 45, which overhangs the right-rear portion of "slot 44, prevents the rightwardly shifted camming member from falling into the slot. This keeps the platen and paper raised and permits the trailing edge 43 of the mask aperture to pass under the front edge of the paper out of engagement therewith. A slight additional forward movement of mask brings a trailing cam surface 47 of shoulder 45 under the right-hand edge of camming member 36. The weight of the platen and paper on camming member 36 causes surface 47 to earn member 36 to the left (as viewed in Fig. 2), along with the platen and paper. Member 36 then falls through slot 44 of the mask and seats in notch 13 of base 10, thereby lowering the platen and paper to their horizontal positions, as shown in Figs. 3 and 5. The location of surface 47 on shoulder 45 is such that the platen and paper are permitted to fall to their horizontal positions only after the trailing edge 43 of the mask aperture has passed beneath the front edge 35 of the paper. At approximately this same position of mask 40, a pair of upper and lower depressions 48 near the leading edge of the mask engage a corresponding pair of spring-operated detents 62 which are mounted on a rear wall 60 of the printer cabinet. Detents 62 retain the mask in its seated position in which a short length of the trailing edge of the mask, including a gripping slot 46 (Fig. 1), extends through slot 52 (Figs. 3 and 5) in the front wall or door of the cabinet. 7

When it is desired to remove the mask from the cabinet the operator grips that portion of the mask extending outside of the printer cabinet and pulls the mask out of slot 52. The rear edge of slot 44 in the mask engages an inclined lower rear surface '39 of carnming member 36 and raises the camming member, platen 4 the combination of: a printing mask adapted to be moved from a position away from said paper to a position adjacent said paper, said mask having a portion thereof adapted to cooperate with a portion of said platen for moving said platen during at least a part of the movement of said mask; and a connection between said platen and said paper for moving the paper away from said printing position in response to said movement of the platen.

2. The combination defined in claim 1, wherein said cooperating portion of the platen comprises a camming surface integral with the platen.

3. The combination defined in claim 1, with means including said cooperating portion of the platen for restoring said platen to its normal position in response to additional movement of said mask.

4. In a photographic printer adapted to hold a length of printing paper and having a platen normally positioned for maintaining said paper in a printing position, the combination of: a. camming member on said platen; a mask adapted to be moved toward said printing position and having a surface cooperating with said camming member to move said platen away from its normal position in response to movement of the mask toward said printing position; a connection between said platen and said paper to move the paper from said printing position in response to said movement of the platen; and means for restoring said platen to its normal position in response to additional movement of said mask toward said printing position, said restoring means inclnuding a slot in the mask for receiving said camming member.

5. The combination defined in claim 4, with: means including said camming member and said mask for partially rotating said platen in its own plane in response to partial insertion of said mask; a shoulder overlying a portion of the slot in said mask to prevent said camming member from entering said last-named slot during said partial insertion; and a camming surface on said shoulder constituting a part of said restoring means and adapted to cooperate with said camming member to counter-rotate said platen in response to further insertion of said mask.

6. In a photo-graphic printer having a cabinet with light-tight walls and having printing means mounted in said cabinet, said printing means including a length of printing paper and a platen normally positioned to maintain said paper in a printing position, the combination of: a light-tight slot in one wall of said cabinet; a mask adapted to be inserted into said cabinet through said slot; guiding means in said cabinet for guiding an inserted mask along a predetermined path; means located along said path and adapted to cooperate with said inserted mask to move said platen away from its normal position in response to the insertion of said mask; and means connected to said platen for moving said paper away from said printing position in response to said movement of the platen.

7. In a photographic printer having a cabinet with light-tight walls and having printing means mounted in said cabinet, said printing means including a length of printing paper and a platen normally positioned to main tain said paper in a printing position, the combination of: a light-tight slot in said cabinet; a mask adapted to be inserted into said cabinet through said slot; guiding means in said cabinet for guiding an inserted mask along a predetermined path; means located along said path and adapted to cooperate with said inserted mask to move said platen away from its normal position in response to partial insertion of the mask; means connected to said platen for moving said paper away from said printing position in response-to said movement of the platen; and means including said cooperating means for restoring said platen to its normal position and for restoring said paper to the printing position in response to further insertion of the mask into said cabinet.

8. The combination defined in claim 7, wherein said cooperating means includes a camming member integral with the platen.

9. In a photographic printer having a cabinet with light-tight walls and having printing means mounted in said cabinet, said printing means including a length of printing paper and a platen normally positioned to maintain said paper in a printing position, the combination of: a light-tight slot in said cabinet; a mask adapted to be inserted into said cabinet through said slot; guiding means in said cabinet for guiding an inserted mask along a predetermined path; a camming member integral With said platen and adapted to cooperate with said inserted mask to move the platen away from its normal position in response to partial insertion of the mask; means connected to said platen for moving said paper away from said printing position in response to said movement of the platen; and means for restoring said platen to its normal position and for restoring said paper to the printing position in response to further insertion of the mask into said cabinet, said restoring means including a slot in said mask for receiving said camming member.

10. The combination defined in claim 9, with: means including said camming member and said mask for partially rotating said platen in its own plane in response to partial insertion of said mask; a shoulder overlying a portion of the slot in said mask to prevent said camming member from entering said last-named slot during said partial insertion; and a camming surface on said shoulder constituting a part of said restoring means and adapted to cooperate with said camming member to counterrotate said platen in response to further insertion of said mask.

11. In a photographic printer adapted to hold a length of printing paper, the combination of: a platen having first and second positions and having a first surface engageable with said paper for maintaining said paper in a printing position when the platen is in its first position; a printing mask adapted to be moved from a position away from said paper to a position adjacent said paper, said mask cooperating with said platen for moving the platen to its second position during at least a part of the movement of said mask; and a second surface on said platen engageable with said paper for moving the paper away from said printing position in response to said movement of the platen.

12. The combination defined in claim 11, wherein said platen comprises: (1) a substantially flat member, at least a portion of one face of said member constituting said first surface; and (2) at least one arm connected to said member and forming a slot between the arm and said member for receiving said paper, at least a portion of said arm constituting said second surface.

References Cited in the file of this patent UNITED STATES PATENTS 1,894,005 Rose J an. 10, 1933 2,207,211 Worlatscheck July 9, 1940 2,589,680 Denny Mar. 18, 1952 

